C++ GrGLSLFPFragmentBuilder::codeAppend方法代码示例

    void emitCode(EmitArgs& args) override {

        GrBlurredEdgeFP::Mode mode = args.fFp.cast<GrBlurredEdgeFP>().mode();

        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

        fragBuilder->codeAppendf("vec4 color = %s;", args.fInputColor);
        if (!args.fGpImplementsDistanceVector) {
            fragBuilder->codeAppendf("// assuming interpolant is set in vertex colors\n");
            fragBuilder->codeAppendf("float factor = 1.0 - color.b;");
        } else {
            fragBuilder->codeAppendf("// using distance to edge to compute interpolant\n");
            fragBuilder->codeAppend("float radius = color.r*256.0*64.0 + color.g*64.0;");
            fragBuilder->codeAppend("float pad = color.b*64.0;");

            fragBuilder->codeAppendf("float factor = 1.0 - clamp((%s.z - pad)/radius, 0.0, 1.0);",
                                     fragBuilder->distanceVectorName());
        }
        switch (mode) {
            case GrBlurredEdgeFP::kGaussian_Mode:
                fragBuilder->codeAppend("factor = exp(-factor * factor * 4.0) - 0.018;");
                break;
            case GrBlurredEdgeFP::kSmoothstep_Mode:
                fragBuilder->codeAppend("factor = smoothstep(factor, 0.0, 1.0);");
                break;
        }
        if (!args.fGpImplementsDistanceVector) {
            fragBuilder->codeAppendf("%s = vec4(factor*color.g);", args.fOutputColor);
        } else {
            fragBuilder->codeAppendf("%s = vec4(factor*color.a);", args.fOutputColor);
        }
    }

        void onEmitCode(EmitArgs& args) override {
            GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
            GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;

            // add uniform
            const char* xformUniName = nullptr;
            fXformUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kMat22f_GrSLType,
                                                   kDefault_GrSLPrecision, "Xform", &xformUniName);

            SkString dstNormalColorName("dstNormalColor");
            this->emitChild(0, nullptr, &dstNormalColorName, args);
            fragBuilder->codeAppendf("vec3 normal = normalize(%s.rgb - vec3(0.5));",
                                     dstNormalColorName.c_str());

            // If there's no x & y components, return (0, 0, +/- 1) instead to avoid division by 0
            fragBuilder->codeAppend( "if (abs(normal.z) > 0.999) {");
            fragBuilder->codeAppendf("    %s = normalize(vec4(0.0, 0.0, normal.z, 0.0));",
                    args.fOutputColor);
            // Else, Normalizing the transformed X and Y, while keeping constant both Z and the
            // vector's angle in the XY plane. This maintains the "slope" for the surface while
            // appropriately rotating the normal regardless of any anisotropic scaling that occurs.
            // Here, we call 'scaling factor' the number that must divide the transformed X and Y so
            // that the normal's length remains equal to 1.
            fragBuilder->codeAppend( "} else {");
            fragBuilder->codeAppendf("    vec2 transformed = %s * normal.xy;",
                    xformUniName);
            fragBuilder->codeAppend( "    float scalingFactorSquared = "
                                                 "( (transformed.x * transformed.x) "
                                                   "+ (transformed.y * transformed.y) )"
                                                 "/(1.0 - (normal.z * normal.z));");
            fragBuilder->codeAppendf("    %s = vec4(transformed*inversesqrt(scalingFactorSquared),"
                                                   "normal.z, 0.0);",
                    args.fOutputColor);
            fragBuilder->codeAppend( "}");
        }

void GrCircleBlurFragmentProcessor::GLSLProcessor::emitCode(EmitArgs& args) {
    const char *dataName;

    // The data is formatted as:
    // x,y  - the center of the circle
    // z    - inner radius that should map to 0th entry in the texture.
    // w    - the inverse of the distance over which the texture is stretched.
    fDataUniform = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec4f_GrSLType,
                                                    kDefault_GrSLPrecision,
                                                    "data",
                                                    &dataName);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

    if (args.fInputColor) {
        fragBuilder->codeAppendf("vec4 src=%s;", args.fInputColor);
    } else {
        fragBuilder->codeAppendf("vec4 src=vec4(1);");
    }

    // We just want to compute "(length(vec) - %s.z + 0.5) * %s.w" but need to rearrange
    // for precision.
    fragBuilder->codeAppendf("vec2 vec = vec2( (sk_FragCoord.x - %s.x) * %s.w, "
                                              "(sk_FragCoord.y - %s.y) * %s.w );",
                             dataName, dataName, dataName, dataName);
    fragBuilder->codeAppendf("float dist = length(vec) + (0.5 - %s.z) * %s.w;",
                             dataName, dataName);

    fragBuilder->codeAppendf("float intensity = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "vec2(dist, 0.5)");
    fragBuilder->codeAppend(".a;");

    fragBuilder->codeAppendf("%s = src * intensity;\n", args.fOutputColor );
}

 void emitCode(EmitArgs& args) override {
     GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
     fragBuilder->codeAppendf("%s = ", args.fOutputColor);
     fragBuilder->appendTextureLookupAndModulate(args.fInputColor,
                                               args.fSamplers[0],
                                               args.fCoords[0].c_str(),
                                               args.fCoords[0].getType());
     fragBuilder->codeAppend(";");
 }

    void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
        const GrBitmapTextGeoProc& btgp = args.fGP.cast<GrBitmapTextGeoProc>();

        GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
        GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
        GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;

        // emit attributes
        varyingHandler->emitAttributes(btgp);

        const char* atlasSizeInvName;
        fAtlasSizeInvUniform = uniformHandler->addUniform(kVertex_GrShaderFlag,
                                                          kFloat2_GrSLType,
                                                          kHigh_GrSLPrecision,
                                                          "AtlasSizeInv",
                                                          &atlasSizeInvName);

        GrGLSLVarying uv(kFloat2_GrSLType);
        GrSLType texIdxType = args.fShaderCaps->integerSupport() ? kInt_GrSLType : kFloat_GrSLType;
        GrGLSLVarying texIdx(texIdxType);
        append_index_uv_varyings(args, btgp.inTextureCoords().name(), atlasSizeInvName, &uv,
                                 &texIdx, nullptr);

        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
        // Setup pass through color
        if (btgp.hasVertexColor()) {
            varyingHandler->addPassThroughAttribute(btgp.inColor(), args.fOutputColor);
        } else {
            this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor,
                                    &fColorUniform);
        }

        // Setup position
        gpArgs->fPositionVar = btgp.inPosition().asShaderVar();

        // emit transforms
        this->emitTransforms(vertBuilder,
                             varyingHandler,
                             uniformHandler,
                             btgp.inPosition().asShaderVar(),
                             btgp.localMatrix(),
                             args.fFPCoordTransformHandler);

        fragBuilder->codeAppend("half4 texColor;");
        append_multitexture_lookup(args, btgp.numTextureSamplers(),
                                   texIdx, uv.fsIn(), "texColor");

        if (btgp.maskFormat() == kARGB_GrMaskFormat) {
            // modulate by color
            fragBuilder->codeAppendf("%s = %s * texColor;", args.fOutputColor, args.fOutputColor);
            fragBuilder->codeAppendf("%s = half4(1);", args.fOutputCoverage);
        } else {
            fragBuilder->codeAppendf("%s = texColor;", args.fOutputCoverage);
        }
    }

void GrColorCubeEffect::GLSLProcessor::emitCode(EmitArgs& args) {
    if (nullptr == args.fInputColor) {
        args.fInputColor = "vec4(1)";
    }

    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fColorCubeSizeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                   kFloat_GrSLType, kDefault_GrSLPrecision,
                                                   "Size");
    const char* colorCubeSizeUni = uniformHandler->getUniformCStr(fColorCubeSizeUni);
    fColorCubeInvSizeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                      kFloat_GrSLType, kDefault_GrSLPrecision,
                                                      "InvSize");
    const char* colorCubeInvSizeUni = uniformHandler->getUniformCStr(fColorCubeInvSizeUni);

    const char* nonZeroAlpha = "nonZeroAlpha";
    const char* unPMColor = "unPMColor";
    const char* cubeIdx = "cubeIdx";
    const char* cCoords1 = "cCoords1";
    const char* cCoords2 = "cCoords2";

    // Note: if implemented using texture3D in OpenGL ES older than OpenGL ES 3.0,
    //       the shader might need "#extension GL_OES_texture_3D : enable".

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

    // Unpremultiply color
    fragBuilder->codeAppendf("\tfloat %s = max(%s.a, 0.00001);\n", nonZeroAlpha, args.fInputColor);
    fragBuilder->codeAppendf("\tvec4 %s = vec4(%s.rgb / %s, %s);\n",
                             unPMColor, args.fInputColor, nonZeroAlpha, nonZeroAlpha);

    // Fit input color into the cube.
    fragBuilder->codeAppendf(
        "vec3 %s = vec3(%s.rg * vec2((%s - 1.0) * %s) + vec2(0.5 * %s), %s.b * (%s - 1.0));\n",
        cubeIdx, unPMColor, colorCubeSizeUni, colorCubeInvSizeUni, colorCubeInvSizeUni,
        unPMColor, colorCubeSizeUni);

    // Compute y coord for for texture fetches.
    fragBuilder->codeAppendf("vec2 %s = vec2(%s.r, (floor(%s.b) + %s.g) * %s);\n",
                             cCoords1, cubeIdx, cubeIdx, cubeIdx, colorCubeInvSizeUni);
    fragBuilder->codeAppendf("vec2 %s = vec2(%s.r, (ceil(%s.b) + %s.g) * %s);\n",
                             cCoords2, cubeIdx, cubeIdx, cubeIdx, colorCubeInvSizeUni);

    // Apply the cube.
    fragBuilder->codeAppendf("%s = vec4(mix(", args.fOutputColor);
    fragBuilder->appendTextureLookup(args.fSamplers[0], cCoords1);
    fragBuilder->codeAppend(".bgr, ");
    fragBuilder->appendTextureLookup(args.fSamplers[0], cCoords2);

    // Premultiply color by alpha. Note that the input alpha is not modified by this shader.
    fragBuilder->codeAppendf(".bgr, fract(%s.b)) * vec3(%s), %s.a);\n",
                             cubeIdx, nonZeroAlpha, args.fInputColor);
}

void GrGLConvexPolyEffect::emitCode(EmitArgs& args) {
    const GrConvexPolyEffect& cpe = args.fFp.cast<GrConvexPolyEffect>();

    const char *edgeArrayName;
    fEdgeUniform = args.fUniformHandler->addUniformArray(kFragment_GrShaderFlag,
                                                         kVec3f_GrSLType,
                                                         kDefault_GrSLPrecision,
                                                         "edges",
                                                         cpe.getEdgeCount(),
                                                         &edgeArrayName);
    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    fragBuilder->codeAppend("\t\tfloat alpha = 1.0;\n");
    fragBuilder->codeAppend("\t\tfloat edge;\n");
    const char* fragmentPos = fragBuilder->fragmentPosition();
    for (int i = 0; i < cpe.getEdgeCount(); ++i) {
        fragBuilder->codeAppendf("\t\tedge = dot(%s[%d], vec3(%s.x, %s.y, 1));\n",
                                 edgeArrayName, i, fragmentPos, fragmentPos);
        if (GrProcessorEdgeTypeIsAA(cpe.getEdgeType())) {
            fragBuilder->codeAppend("\t\tedge = clamp(edge, 0.0, 1.0);\n");
        } else {
            fragBuilder->codeAppend("\t\tedge = edge >= 0.5 ? 1.0 : 0.0;\n");
        }
        fragBuilder->codeAppend("\t\talpha *= edge;\n");
    }

    if (GrProcessorEdgeTypeIsInverseFill(cpe.getEdgeType())) {
        fragBuilder->codeAppend("\talpha = 1.0 - alpha;\n");
    }
    fragBuilder->codeAppendf("\t%s = %s;\n", args.fOutputColor,
                             (GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}

void GrGLAlphaThresholdFragmentProcessor::emitCode(EmitArgs& args) {
    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fInnerThresholdVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kFloat_GrSLType, kDefault_GrSLPrecision,
                                                    "inner_threshold");
    fOuterThresholdVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kFloat_GrSLType, kDefault_GrSLPrecision,
                                                    "outer_threshold");

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
    SkString maskCoords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 1);

    fragBuilder->codeAppendf("vec2 coord = %s;", coords2D.c_str());
    fragBuilder->codeAppendf("vec2 mask_coord = %s;", maskCoords2D.c_str());
    fragBuilder->codeAppend("vec4 input_color = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "coord");
    fragBuilder->codeAppend(";");
    fragBuilder->codeAppend("vec4 mask_color = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[1], "mask_coord");
    fragBuilder->codeAppend(";");

    fragBuilder->codeAppendf("float inner_thresh = %s;",
                             uniformHandler->getUniformCStr(fInnerThresholdVar));
    fragBuilder->codeAppendf("float outer_thresh = %s;",
                             uniformHandler->getUniformCStr(fOuterThresholdVar));
    fragBuilder->codeAppend("float mask = mask_color.a;");

    fragBuilder->codeAppend("vec4 color = input_color;");
    fragBuilder->codeAppend("if (mask < 0.5) {"
                            "if (color.a > outer_thresh) {"
                            "float scale = outer_thresh / color.a;"
                            "color.rgb *= scale;"
                            "color.a = outer_thresh;"
                            "}"
                            "} else if (color.a < inner_thresh) {"
                            "float scale = inner_thresh / max(0.001, color.a);"
                            "color.rgb *= scale;"
                            "color.a = inner_thresh;"
                            "}");

    fragBuilder->codeAppendf("%s = %s;", args.fOutputColor,
                             (GrGLSLExpr4(args.fInputColor) * GrGLSLExpr4("color")).c_str());
}

void GrGLCircleBlurFragmentProcessor::emitCode(EmitArgs& args) {

    const char *dataName;

    // The data is formatted as:
    // x,y  - the center of the circle
    // z    - the distance at which the intensity starts falling off (e.g., the start of the table)
    // w    - the inverse of the profile texture size
    fDataUniform = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec4f_GrSLType,
                                                    kDefault_GrSLPrecision,
                                                    "data",
                                                    &dataName);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    const char *fragmentPos = fragBuilder->fragmentPosition();

    if (args.fInputColor) {
        fragBuilder->codeAppendf("vec4 src=%s;", args.fInputColor);
    } else {
        fragBuilder->codeAppendf("vec4 src=vec4(1);");
    }

    // We just want to compute "length(vec) - %s.z + 0.5) * %s.w" but need to rearrange
    // for precision
    fragBuilder->codeAppendf("vec2 vec = vec2( (%s.x - %s.x) * %s.w , (%s.y - %s.y) * %s.w );",
                             fragmentPos, dataName, dataName,
                             fragmentPos, dataName, dataName);
    fragBuilder->codeAppendf("float dist = length(vec) + ( 0.5 - %s.z ) * %s.w;",
                             dataName, dataName);

    fragBuilder->codeAppendf("float intensity = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "vec2(dist, 0.5)");
    fragBuilder->codeAppend(".a;");

    fragBuilder->codeAppendf("%s = src * intensity;\n", args.fOutputColor );
}

void GrGLMagnifierEffect::emitCode(EmitArgs& args) {
    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fOffsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                            kVec2f_GrSLType, kDefault_GrSLPrecision,
                                            "Offset");
    fInvZoomVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                             kVec2f_GrSLType, kDefault_GrSLPrecision,
                                             "InvZoom");
    fInvInsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                              kVec2f_GrSLType, kDefault_GrSLPrecision,
                                              "InvInset");
    fBoundsVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                            kVec4f_GrSLType, kDefault_GrSLPrecision,
                                            "Bounds");

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
    fragBuilder->codeAppendf("\t\tvec2 coord = %s;\n", coords2D.c_str());
    fragBuilder->codeAppendf("\t\tvec2 zoom_coord = %s + %s * %s;\n",
                             uniformHandler->getUniformCStr(fOffsetVar),
                             coords2D.c_str(),
                             uniformHandler->getUniformCStr(fInvZoomVar));
    const char* bounds = uniformHandler->getUniformCStr(fBoundsVar);
    fragBuilder->codeAppendf("\t\tvec2 delta = (coord - %s.xy) * %s.zw;\n", bounds, bounds);
    fragBuilder->codeAppendf("\t\tdelta = min(delta, vec2(1.0, 1.0) - delta);\n");
    fragBuilder->codeAppendf("\t\tdelta = delta * %s;\n",
                             uniformHandler->getUniformCStr(fInvInsetVar));

    fragBuilder->codeAppend("\t\tfloat weight = 0.0;\n");
    fragBuilder->codeAppend("\t\tif (delta.s < 2.0 && delta.t < 2.0) {\n");
    fragBuilder->codeAppend("\t\t\tdelta = vec2(2.0, 2.0) - delta;\n");
    fragBuilder->codeAppend("\t\t\tfloat dist = length(delta);\n");
    fragBuilder->codeAppend("\t\t\tdist = max(2.0 - dist, 0.0);\n");
    fragBuilder->codeAppend("\t\t\tweight = min(dist * dist, 1.0);\n");
    fragBuilder->codeAppend("\t\t} else {\n");
    fragBuilder->codeAppend("\t\t\tvec2 delta_squared = delta * delta;\n");
    fragBuilder->codeAppend("\t\t\tweight = min(min(delta_squared.x, delta_squared.y), 1.0);\n");
    fragBuilder->codeAppend("\t\t}\n");

    fragBuilder->codeAppend("\t\tvec2 mix_coord = mix(coord, zoom_coord, weight);\n");
    fragBuilder->codeAppend("\t\tvec4 output_color = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "mix_coord");
    fragBuilder->codeAppend(";\n");

    fragBuilder->codeAppendf("\t\t%s = output_color;", args.fOutputColor);
    SkString modulate;
    GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
    fragBuilder->codeAppend(modulate.c_str());
}

void GrGLMatrixConvolutionEffect::emitCode(EmitArgs& args) {
    const GrMatrixConvolutionEffect& mce = args.fFp.cast<GrMatrixConvolutionEffect>();
    const GrTextureDomain& domain = mce.domain();

    int kWidth = mce.kernelSize().width();
    int kHeight = mce.kernelSize().height();

    int arrayCount = (kWidth * kHeight + 3) / 4;
    SkASSERT(4 * arrayCount >= kWidth * kHeight);

    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fImageIncrementUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
                                                    "ImageIncrement");
    fKernelUni = uniformHandler->addUniformArray(kFragment_GrShaderFlag, kHalf4_GrSLType,
                                                 "Kernel",
                                                 arrayCount);
    fKernelOffsetUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
                                                  "KernelOffset");
    fGainUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf_GrSLType, "Gain");
    fBiasUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf_GrSLType, "Bias");

    const char* kernelOffset = uniformHandler->getUniformCStr(fKernelOffsetUni);
    const char* imgInc = uniformHandler->getUniformCStr(fImageIncrementUni);
    const char* kernel = uniformHandler->getUniformCStr(fKernelUni);
    const char* gain = uniformHandler->getUniformCStr(fGainUni);
    const char* bias = uniformHandler->getUniformCStr(fBiasUni);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);
    fragBuilder->codeAppend("half4 sum = half4(0, 0, 0, 0);");
    fragBuilder->codeAppendf("float2 coord = %s - %s * %s;", coords2D.c_str(), kernelOffset, imgInc);
    fragBuilder->codeAppend("half4 c;");

    const char* kVecSuffix[4] = { ".x", ".y", ".z", ".w" };
    for (int y = 0; y < kHeight; y++) {
        for (int x = 0; x < kWidth; x++) {
            GrGLSLShaderBuilder::ShaderBlock block(fragBuilder);
            int offset = y*kWidth + x;

            fragBuilder->codeAppendf("half k = %s[%d]%s;", kernel, offset / 4,
                                     kVecSuffix[offset & 0x3]);
            SkString coord;
            coord.printf("coord + half2(%d, %d) * %s", x, y, imgInc);
            fDomain.sampleTexture(fragBuilder,
                                  uniformHandler,
                                  args.fShaderCaps,
                                  domain,
                                  "c",
                                  coord,
                                  args.fTexSamplers[0]);
            if (!mce.convolveAlpha()) {
                fragBuilder->codeAppend("c.rgb /= c.a;");
                fragBuilder->codeAppend("c.rgb = clamp(c.rgb, 0.0, 1.0);");
            }
            fragBuilder->codeAppend("sum += c * k;");
        }
    }
    if (mce.convolveAlpha()) {
        fragBuilder->codeAppendf("%s = sum * %s + %s;", args.fOutputColor, gain, bias);
        fragBuilder->codeAppendf("%s.a = clamp(%s.a, 0, 1);", args.fOutputColor, args.fOutputColor);
        fragBuilder->codeAppendf("%s.rgb = clamp(%s.rgb, 0.0, %s.a);",
                                 args.fOutputColor, args.fOutputColor, args.fOutputColor);
    } else {
        fDomain.sampleTexture(fragBuilder,
                              uniformHandler,
                              args.fShaderCaps,
                              domain,
                              "c",
                              coords2D,
                              args.fTexSamplers[0]);
        fragBuilder->codeAppendf("%s.a = c.a;", args.fOutputColor);
        fragBuilder->codeAppendf("%s.rgb = clamp(sum.rgb * %s + %s, 0, 1);", args.fOutputColor, gain, bias);
        fragBuilder->codeAppendf("%s.rgb *= %s.a;", args.fOutputColor, args.fOutputColor);
    }
    fragBuilder->codeAppendf("%s *= %s;\n", args.fOutputColor, args.fInputColor);
}

    void emitCode(EmitArgs& args) override {
        const TwoPointConicalEffect& effect = args.fFp.cast<TwoPointConicalEffect>();
        GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
        this->emitUniforms(uniformHandler, effect);
        fParamUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
                                               "Conical2FSParams");

        SkString p0; // 1 / r1
        SkString p1; // f = focalX = r0 / (r0 - r1)
        p0.appendf("%s.x", uniformHandler->getUniformVariable(fParamUni).getName().c_str());
        p1.appendf("%s.y", uniformHandler->getUniformVariable(fParamUni).getName().c_str());
        const char* tName = "t"; // the gradient

        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
        SkString coords2D = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);
        const char* p = coords2D.c_str();

        if (effect.isFocalOnCircle()) {
            fragBuilder->codeAppendf("half x_t = dot(%s, %s) / %s.x;", p, p, p);
        } else if (effect.isWellBehaved()) {
            fragBuilder->codeAppendf("half x_t = length(%s) - %s.x * %s;", p, p, p0.c_str());
        } else {
            char sign = (effect.isSwapped() || !effect.isRadiusIncreasing()) ? '-' : ' ';
            fragBuilder->codeAppendf("half temp = %s.x * %s.x - %s.y * %s.y;", p, p, p, p);
            // Initialize x_t to illegal state
            fragBuilder->codeAppendf("half x_t = -1;");

            // Only do sqrt if temp >= 0; this is significantly slower than checking temp >= 0 in
            // the if statement that checks r(t) >= 0. But GPU may break if we sqrt a negative
            // float. (Although I havevn't observed that on any devices so far, and the old approach
            // also does sqrt negative value without a check.) If the performance is really
            // critical, maybe we should just compute the area where temp and x_t are always
            // valid and drop all these ifs.
            fragBuilder->codeAppendf("if (temp >= 0) {");
            fragBuilder->codeAppendf("x_t = (%csqrt(temp) - %s.x * %s);", sign, p, p0.c_str());
            fragBuilder->codeAppendf("}");
        }

        // empty sign is positive
        char sign = effect.isRadiusIncreasing() ? ' ' : '-';

        // "+ 0" is much faster than "+ p1" so we specialize the natively focal case where p1 = 0.
        fragBuilder->codeAppendf("half %s = %cx_t + %s;", tName, sign,
                effect.isNativelyFocal() ? "0" : p1.c_str());

        if (!effect.isWellBehaved()) {
            // output will default to transparent black (we simply won't write anything
            // else to it if invalid, instead of discarding or returning prematurely)
            fragBuilder->codeAppendf("%s = half4(0.0,0.0,0.0,0.0);", args.fOutputColor);
            fragBuilder->codeAppendf("if (x_t > 0.0) {");
        }

        if (effect.isSwapped()) {
            fragBuilder->codeAppendf("%s = 1 - %s;", tName, tName);
        }

        this->emitColor(fragBuilder,
                        uniformHandler,
                        args.fShaderCaps,
                        effect,
                        tName,
                        args.fOutputColor,
                        args.fInputColor,
                        args.fTexSamplers);
        if (!effect.isWellBehaved()) {
            fragBuilder->codeAppend("};");
        }
    }

    void emitCode(EmitArgs& args) override {
        const GrConfigConversionEffect& cce = args.fFp.cast<GrConfigConversionEffect>();
        const GrSwizzle& swizzle = cce.swizzle();
        GrConfigConversionEffect::PMConversion pmConversion = cce.pmConversion();

        // Using highp for GLES here in order to avoid some precision issues on specific GPUs.
        GrGLSLShaderVar tmpVar("tmpColor", kVec4f_GrSLType, 0, kHigh_GrSLPrecision);
        SkString tmpDecl;
        tmpVar.appendDecl(args.fGLSLCaps, &tmpDecl);

        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

        fragBuilder->codeAppendf("%s;", tmpDecl.c_str());

        fragBuilder->codeAppendf("%s = ", tmpVar.c_str());
        fragBuilder->appendTextureLookup(args.fTexSamplers[0], args.fCoords[0].c_str(),
                                       args.fCoords[0].getType());
        fragBuilder->codeAppend(";");

        if (GrConfigConversionEffect::kNone_PMConversion == pmConversion) {
            SkASSERT(GrSwizzle::RGBA() != swizzle);
            fragBuilder->codeAppendf("%s = %s.%s;", args.fOutputColor, tmpVar.c_str(),
                                     swizzle.c_str());
        } else {
            switch (pmConversion) {
                case GrConfigConversionEffect::kMulByAlpha_RoundUp_PMConversion:
                    fragBuilder->codeAppendf(
                        "%s = vec4(ceil(%s.rgb * %s.a * 255.0) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str());
                    break;
                case GrConfigConversionEffect::kMulByAlpha_RoundDown_PMConversion:
                    // Add a compensation(0.001) here to avoid the side effect of the floor operation.
                    // In Intel GPUs, the integer value converted from floor(%s.r * 255.0) / 255.0
                    // is less than the integer value converted from  %s.r by 1 when the %s.r is
                    // converted from the integer value 2^n, such as 1, 2, 4, 8, etc.
                    fragBuilder->codeAppendf(
                        "%s = vec4(floor(%s.rgb * %s.a * 255.0 + 0.001) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str());

                    break;
                case GrConfigConversionEffect::kDivByAlpha_RoundUp_PMConversion:
                    fragBuilder->codeAppendf(
                        "%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(ceil(%s.rgb / %s.a * 255.0) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(),
                        tmpVar.c_str());
                    break;
                case GrConfigConversionEffect::kDivByAlpha_RoundDown_PMConversion:
                    fragBuilder->codeAppendf(
                        "%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(floor(%s.rgb / %s.a * 255.0) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(),
                        tmpVar.c_str());
                    break;
                default:
                    SkFAIL("Unknown conversion op.");
                    break;
            }
            fragBuilder->codeAppendf("%s = %s.%s;", args.fOutputColor, tmpVar.c_str(),
                                     swizzle.c_str());
        }
        SkString modulate;
        GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
        fragBuilder->codeAppend(modulate.c_str());
    }

void GLCircularRRectEffect::emitCode(EmitArgs& args) {
    const CircularRRectEffect& crre = args.fFp.cast<CircularRRectEffect>();
    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    const char *rectName;
    const char *radiusPlusHalfName;
    // The inner rect is the rrect bounds inset by the radius. Its left, top, right, and bottom
    // edges correspond to components x, y, z, and w, respectively. When a side of the rrect has
    // only rectangular corners, that side's value corresponds to the rect edge's value outset by
    // half a pixel.
    fInnerRectUniform = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf4_GrSLType,
                                                   "innerRect", &rectName);
    // x is (r + .5) and y is 1/(r + .5)
    fRadiusPlusHalfUniform = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
                                                        "radiusPlusHalf", &radiusPlusHalfName);

    // If we're on a device where float != fp32 then the length calculation could overflow.
    SkString clampedCircleDistance;
    if (!args.fShaderCaps->floatIs32Bits()) {
        clampedCircleDistance.printf("clamp(%s.x * (1.0 - length(dxy * %s.y)), 0.0, 1.0);",
                                     radiusPlusHalfName, radiusPlusHalfName);
    } else {
        clampedCircleDistance.printf("clamp(%s.x - length(dxy), 0.0, 1.0);", radiusPlusHalfName);
    }

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    // At each quarter-circle corner we compute a vector that is the offset of the fragment position
    // from the circle center. The vector is pinned in x and y to be in the quarter-plane relevant
    // to that corner. This means that points near the interior near the rrect top edge will have
    // a vector that points straight up for both the TL left and TR corners. Computing an
    // alpha from this vector at either the TR or TL corner will give the correct result. Similarly,
    // fragments near the other three edges will get the correct AA. Fragments in the interior of
    // the rrect will have a (0,0) vector at all four corners. So long as the radius > 0.5 they will
    // correctly produce an alpha value of 1 at all four corners. We take the min of all the alphas.
    // The code below is a simplified version of the above that performs maxs on the vector
    // components before computing distances and alpha values so that only one distance computation
    // need be computed to determine the min alpha.
    //
    // For the cases where one half of the rrect is rectangular we drop one of the x or y
    // computations, compute a separate rect edge alpha for the rect side, and mul the two computed
    // alphas together.
    switch (crre.getCircularCornerFlags()) {
        case CircularRRectEffect::kAll_CornerFlags:
            fragBuilder->codeAppendf("float2 dxy0 = %s.xy - sk_FragCoord.xy;", rectName);
            fragBuilder->codeAppendf("float2 dxy1 = sk_FragCoord.xy - %s.zw;", rectName);
            fragBuilder->codeAppend("float2 dxy = max(max(dxy0, dxy1), 0.0);");
            fragBuilder->codeAppendf("half alpha = %s;", clampedCircleDistance.c_str());
            break;
        case CircularRRectEffect::kTopLeft_CornerFlag:
            fragBuilder->codeAppendf("float2 dxy = max(%s.xy - sk_FragCoord.xy, 0.0);",
                                     rectName);
            fragBuilder->codeAppendf("half rightAlpha = clamp(%s.z - sk_FragCoord.x, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half bottomAlpha = clamp(%s.w - sk_FragCoord.y, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half alpha = bottomAlpha * rightAlpha * %s;",
                                     clampedCircleDistance.c_str());
            break;
        case CircularRRectEffect::kTopRight_CornerFlag:
            fragBuilder->codeAppendf("float2 dxy = max(float2(sk_FragCoord.x - %s.z, "
                                                             "%s.y - sk_FragCoord.y), 0.0);",
                                     rectName, rectName);
            fragBuilder->codeAppendf("half leftAlpha = clamp(sk_FragCoord.x - %s.x, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half bottomAlpha = clamp(%s.w - sk_FragCoord.y, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half alpha = bottomAlpha * leftAlpha * %s;",
                                     clampedCircleDistance.c_str());
            break;
        case CircularRRectEffect::kBottomRight_CornerFlag:
            fragBuilder->codeAppendf("float2 dxy = max(sk_FragCoord.xy - %s.zw, 0.0);",
                                     rectName);
            fragBuilder->codeAppendf("half leftAlpha = clamp(sk_FragCoord.x - %s.x, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half topAlpha = clamp(sk_FragCoord.y - %s.y, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half alpha = topAlpha * leftAlpha * %s;",
                                     clampedCircleDistance.c_str());
            break;
        case CircularRRectEffect::kBottomLeft_CornerFlag:
            fragBuilder->codeAppendf("float2 dxy = max(float2(%s.x - sk_FragCoord.x, "
                                                             "sk_FragCoord.y - %s.w), 0.0);",
                                     rectName, rectName);
            fragBuilder->codeAppendf("half rightAlpha = clamp(%s.z - sk_FragCoord.x, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half topAlpha = clamp(sk_FragCoord.y - %s.y, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half alpha = topAlpha * rightAlpha * %s;",
                                     clampedCircleDistance.c_str());
            break;
        case CircularRRectEffect::kLeft_CornerFlags:
            fragBuilder->codeAppendf("float2 dxy0 = %s.xy - sk_FragCoord.xy;", rectName);
            fragBuilder->codeAppendf("float dy1 = sk_FragCoord.y - %s.w;", rectName);
            fragBuilder->codeAppend("float2 dxy = max(float2(dxy0.x, max(dxy0.y, dy1)), 0.0);");
            fragBuilder->codeAppendf("half rightAlpha = clamp(%s.z - sk_FragCoord.x, 0.0, 1.0);",
                                     rectName);
            fragBuilder->codeAppendf("half alpha = rightAlpha * %s;",
                                     clampedCircleDistance.c_str());
            break;
        case CircularRRectEffect::kTop_CornerFlags:
            fragBuilder->codeAppendf("float2 dxy0 = %s.xy - sk_FragCoord.xy;", rectName);
//.........这里部分代码省略.........

void GrGLConvolutionEffect::emitCode(EmitArgs& args) {
    const GrConvolutionEffect& ce = args.fFp.cast<GrConvolutionEffect>();

    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fImageIncrementUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec2f_GrSLType, kDefault_GrSLPrecision,
                                                    "ImageIncrement");
    if (ce.useBounds()) {
        fBoundsUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                kVec2f_GrSLType, kDefault_GrSLPrecision,
                                                "Bounds");
    }

    int width = Gr1DKernelEffect::WidthFromRadius(ce.radius());

    int arrayCount = (width + 3) / 4;
    SkASSERT(4 * arrayCount >= width);

    fKernelUni = uniformHandler->addUniformArray(kFragment_GrShaderFlag,
                                                 kVec4f_GrSLType, kDefault_GrSLPrecision,
                                                 "Kernel", arrayCount);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);

    fragBuilder->codeAppendf("%s = vec4(0, 0, 0, 0);", args.fOutputColor);

    const GrGLSLShaderVar& kernel = uniformHandler->getUniformVariable(fKernelUni);
    const char* imgInc = uniformHandler->getUniformCStr(fImageIncrementUni);

    fragBuilder->codeAppendf("vec2 coord = %s - %d.0 * %s;", coords2D.c_str(), ce.radius(), imgInc);

    // Manually unroll loop because some drivers don't; yields 20-30% speedup.
    const char* kVecSuffix[4] = { ".x", ".y", ".z", ".w" };
    for (int i = 0; i < width; i++) {
        SkString index;
        SkString kernelIndex;
        index.appendS32(i/4);
        kernel.appendArrayAccess(index.c_str(), &kernelIndex);
        kernelIndex.append(kVecSuffix[i & 0x3]);

        if (ce.useBounds()) {
            // We used to compute a bool indicating whether we're in bounds or not, cast it to a
            // float, and then mul weight*texture_sample by the float. However, the Adreno 430 seems
            // to have a bug that caused corruption.
            const char* bounds = uniformHandler->getUniformCStr(fBoundsUni);
            const char* component = ce.direction() == Gr1DKernelEffect::kY_Direction ? "y" : "x";
            fragBuilder->codeAppendf("if (coord.%s >= %s.x && coord.%s <= %s.y) {",
                                     component, bounds, component, bounds);
        }
        fragBuilder->codeAppendf("\t\t%s += ", args.fOutputColor);
        fragBuilder->appendTextureLookup(args.fTexSamplers[0], "coord");
        fragBuilder->codeAppendf(" * %s;\n", kernelIndex.c_str());
        if (ce.useBounds()) {
            fragBuilder->codeAppend("}");
        }
        fragBuilder->codeAppendf("\t\tcoord += %s;\n", imgInc);
    }

    SkString modulate;
    GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
    fragBuilder->codeAppend(modulate.c_str());
}